DE10109992A1 - Production of polymer dispersions, used as e.g. surface coatings and paints, comprises mixing a polymer, a surfactant and water in a twin-screw extruder - Google Patents

Abstract

Production of polymer dispersions comprises mixing polymer, surfactant and water in twin-screw extruder comprising feed zone, melting zone, two mixing zones and discharge zone. A ring of molten polymer is formed between melting zone and first mixing zone, and seals in the contents of the feed zone. The discharge zone has a pressure-retaining device. The final solids content of dispersion is adjusted by adding water to last mixing zone Production of polymer dispersions with a solids content of 5-95 wt.% comprises mixing at least one polymer, at least one surfactant and water in a twin-screw extruder operating at a screw speed of at least 600 rpm, where: (a) the extruder comprises a feed zone into which the polymer is introduced; a melting zone in which the polymer is melted; a first mixing zone into which part of the water is fed to form a polymer-water mixture; a last mixing zone into which the rest of the water is fed and mixed with the polymer-water mixture; and a discharge zone; (b) the surfactant is introduced into the feed zone, the melting zone, the first mixing zone and/or the last mixing zone; (c) the design of the screws is such that a ring of molten polymer is formed between the melting zone and the first mixing zone and seals in the contents of the feed zone; (d) the discharge zone has a pressure-retaining device; and (e) the final solids content of the dispersion is adjusted by adding the appropriate amount of water to the last mixing zone.

Description

The invention relates to a process for the preparation of polymer dispersions with a final solids content of 5 to 95 wt .-%, in which at least one polymer A, at least one surface-active substance S and water are mixed in a twin-screw extruder, the speed of the extruder screw is at least 600 min ^-1 , and the extruder, viewed in the conveying direction, is essentially constructed from

• - A feed zone in which the polymer A enters the extruder is dosed
• - A melting zone in which polymer A becomes a polymer melt is melted,
• - A first mixing zone in which part of the water enters dosed and with the polymer melt into one Polymer-water mixture is mixed,
• - a final mixing zone, in which the remaining part of the water metered in and mixed with the polymer-water mixture will, and
• - A discharge zone in which the polymer-water mixture is expelled will wear

wherein the surfactant S in the feed zone, the Melting zone, the first or the last mixing zone or in several of these zones of the extruder can be metered in.

The invention further relates to those obtainable by the process Chen polymer dispersions and their use as a surface Chen coating in paints, in construction and corrosion protection, in paper, textile and carpet coating, for La tex foam molded parts, in adhesives or for the production of thermoplastic molding compounds.

The production of aqueous polymer dispersions by Disper yeast of the finished polymer in water (so-called secondary dispersion, in contrast to the primary dispersion, in which the monomers in What be converted to the polymer) by means of a twin screw extruders is well known.

For example, DE-A 41 15 531 describes a method in which the dispersing polymer together with the emulsifier polyvinyl alcohol is first melted and mixed, and this ge melted mixture in one operated at 250 rpm  the two-screw extruder is metered. Downstream Water is metered in and the mixture is extruded. A disadvantage of that sem process is that for melting and mixing the poly an additional device is required with the emulsifier is. In addition, the water must be metered in hot, which the Energy requirements increased. There is also an additional procedure step required, in which the extruded polymer-water Ge mix with water on the final slurry in a homogenizer term solids content is set. So that's the procedure complex and expensive.

EP-A 246 729 teaches a process for the production of so-called "fe "Dispersions with a water content of at most 3% by weight. Here, on a twin-screw extruder made of a polymer, a polymer modified with carboxylic acid groups as an emulsifier and little water made a polymer dispersion that solid or pasty. The dispersion is through a cooling device cooled to a temperature below the boiling point of the water and carried out. This cooling is apparatus and energetic consuming. In order to obtain a liquid aqueous dispersion, the solid dispersion in an additional step in water dis be pergiert, which further complicates the process.

EP-A 972 794 describes a process for producing a dispersion from a thermoplastic molding composition, a C _25-60 fatty acid or its ester as an emulsifier, and water, on a twin-screw extruder with degassing openings. According to example 1, the polymer is melted at 160 ° C. in the extruder and an aqueous solution is added through a degassing opening. The extruder content is cooled to 90 ° C using a chilled static mixer. The document does not say how the extruder content under pressure at 160 ° C should be sealed against the polymer feed and the discharge, both of which are under normal pressure. The process provides solids-free dispersions with a water content of only 3 to 25% by weight. The Scripture teaches that lower solids contents cannot be adjusted. This makes the process inflexible in terms of water content, unclear in terms of pressure seal and expensive in terms of energy consumption.

The task was to remedy the disadvantages described. In particular, the task was to create a method to provide aqueous polymer dispersions in which the under various polymers can be used. Furthermore should The process made both low and solid solids  let fabric-rich dispersions be easily produced, d. H. the Solids content should be variable within wide limits.

Furthermore, the task was to provide a method that without complex cooling of the dispersion at the end of the extruder needs and is therefore independent of the boiling point of the water.

After all, the procedure should already be the final one Let the solids content of the dispersion be adjusted, d. H. the dis persion, which leaves the extruder, should be without downstream Dilution or dispersion in water already the desired Have water content. Mixing the polymer with the Emulsifier, the addition of water and the setting of the final water content should be carried out on a single machine.

Accordingly, the process defined at the outset for the production of polymer dispersions was found. It is characterized

• - That the extruder screws are designed such that in the extruder between the melting zone and the first mixing zone a ring made of melted polymer A (melting ring) trains the subsequent extruder content to feed zone seals off,
• - That the discharge zone contains a pressure maintaining device and
• - That the final solids content of the polymer dispersion be is already set in the last mixing zone by a appropriate amount of water is metered.

The polymer A

All thermoplastic polymers come in as polymers A. costume. Such polymers are used for example in plastic Ta schenbuch, publisher Saechtling, 25th edition, Hanser-Verlag Munich 1992, especially chap. 4, and in the plastic manual, ed. G. Becker and D. Braun, volumes 1 to 11, Hanser-Verlag Munich 1966-1996. In the plastic paperback by Saechtling who also called the sources of supply.

Polymer A is preferably selected from the group of poly oxymethylene, polycarbonates, polyesters, polyolefins, poly acrylates, polymethacrylates, polyamides, vinyl aromatic Polymers, polyarylene ethers, polyurethanes, polyisocyanurates, poly ureas, polylactides, thermoplastic elastomers, halogen containing polymers, polymers containing imide groups, cellulose esters, silicone polymers, or their mixtures or copolymers.  

Process for the preparation of the polymers described below are known to the person skilled in the art and are described in the literature, so that further details are unnecessary here.

1. Polyoxymethylene homo- or copolymers (polyoxymethylenes, POM)

Such polymers are known per se to the person skilled in the art and in described in the literature.

In general, these polymers have at least 50 mol% of the -CH ₂ O- units in the main polymer chain. The homopolymers are generally prepared by polymerizing formaldehyde or trioxane, preferably in the presence of suitable catalysts.

In the context of the invention, polyoxymethylene copolymers are preferred, in particular those which, in addition to the recurring units -CH ₂ O-, up to 50, preferably 0.1 to 20 and in particular 0.3 to 10 mol% of recurring units

contain, wherein R ¹ to R ⁴ independently of one another are a hydrogen atom, a C ₁ to C ₄ alkyl group or a halogen-substituted alkyl group having 1 to 4 C atoms and R ^{5 is} a -CH ₂ -, -CH ₂ O-, a C ₁ - to C ₄ -alkyl or C ₁ - to C ₄ -haloalkyl represent methylene group or a corresponding oxymethylene group and n has a value in the range from 0 to 3. These groups can advantageously be introduced into the copolymers by ring opening of cyclic ethers. Suitable cyclic ethers are, for example, ethylene oxide, 1,2-propylene oxide, 1,2-butylene oxide, 1,3-butylene oxide, 1,3-dioxane, 1,3-dioxolane and 1,3-dioxepane as cyclic ethers and linear oligo- or polyformals such as polydioxolane or polydioxepane as comonomers.

Oxymethylene terpolymers which are also suitable for example by reacting trioxane, one of the above described cyclic ether with a third, bifunctional Monomers are produced. Such bifunctional monomers are z. B. ethylene diglycide, diglycidyl ether and diether  Glycidylene and formaldehyde, dioxane or trioxane in a molar ratio 2: 1 and Diether from 2 mol glycidyl compound and 1 mol one aliphatic diols with 2 to 8 carbon atoms such as Diglycidyl ether of ethylene glycol, 1,4-butanediol, 1,3-butane diol, cyclobutane-1,3-diol, 1,2-propanediol and cyclohexane-1,4-diol.

The preferred polyoxymethylene copolymers have melting points of at least 150 ° C and molecular weights (weight average) Mw im Range from 5000 to 200000, preferably from 7000 to 150,000.

2. Polycarbonate (PC) and polyester

Suitable polycarbonates are known per se. You are e.g. B. ent speaking the method of DE-B-13 00 266 through interfaces polycondensation or according to the method of DE-A-14 95 730 obtainable by reacting biphenyl carbonate with bisphenols. Preferred bisphenol is 2,2-di (4-hydroxyphenyl) propane, im general - as also hereinafter - referred to as bisphenol A.

Instead of bisphenol A, other aromatic Dihydroxy compounds are used, in particular 2,2-di (4-hydroxyphenyl) pentane, 2,6-dihydroxynaphthalene, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl sulfite, 4,4'-dihydroxydiphenylmethane, 1,1-di- (4-hydroxyphenyl) ethane or 4,4-dihydroxydiphenyl as well Mixtures of the aforementioned dihydroxy compounds.

Particularly preferred polycarbonates are those based on Bisphenol A or Bisphenol A together with up to 30 mol% of the 1 aromatic dihydroxy compounds mentioned above. The right The relative viscosity of these polycarbonates is in general Range from 1.1 to 1.5, in particular 1.28 to 1.4 (measured at 25 ° C in a 0.5 wt .-% solution in dichloromethane).

Suitable polyesters are also known per se and are described in the literature. They contain an aromatic ring in the main chain, which originates from an aromatic dicarboxylic acid. The aromatic ring can also be substituted, e.g. B. by halogen such as chlorine and bromine or by C ₁ -C ₄ alkyl groups such as methyl, ethyl, i- or n-propyl and n-, i- or tert-butyl groups.

The polyester can be made by reacting aromatic dicarbon acids, their esters or other ester-forming derivatives ben with aliphatic dihydroxy compounds in known per se Way.  

Preferred dicarboxylic acids are naphthalenedicarboxylic acid, Terephthalic acid and isophthalic acid or mixtures thereof NEN. Up to 10 mol% of the aromatic dicarboxylic acids can by aliphatic or cycloaliphatic dicarboxylic acids such as Adipic acid, azelaic acid, sebacic acid, dodecanedioic acids and Cyclohexanedicarboxylic acids are replaced. From the aliphatic Dihydroxy compounds are diols with 2 to 6 carbon atoms, in particular 1,2-ethanediol, 1,4-butanediol, 1,6-hexanediol, 1,4-hexanediol, 1,4-cyclohexanediol and neopentyl glycol or their Mixtures preferred.

Polyalkylene terephthalates are particularly preferred polyesters, which are derived from alkane diols with 2 to 6 carbon atoms NEN. Of these, polyethylene terephthalate in particular (PET), polyethylene naphthalate and polybutylene terephthalate (PBT) prefers.

The viscosity number of the polyesters is generally in the range from 60 to 200 ml / g (measured in a 0.5% by weight solution in a phenol / o-dichlorobenzene mixture (weight ratio 1: 1 at 25 ° C)).

3. Polyolefins

All polymers of olefins are suitable as polyolefins, ins special polymers of ethylene, propylene, but-1-ene, isobutylene, and 4-methylpentene. "Polymers" should include both homopolymers, as well as copolymers of one of the monomers mentioned as the main mo monomer and other monomers as comonomers. Higher homologs such as witches and octene also come in as comonomers Consideration.

Preferred polyolefins are the homopolymers and copolymers of Ethylene and the homopolymers and copolymers of propylene.

Ethylene polymers

Suitable polyethylene (PE) homopolymers are e.g. B .:

• - PE-LD (LD = low density), available according to the high pressure process (ICI) at 1000 to 3000 bar and 150 to 300 W with oxygen or peroxides as catalysts in autoclaves or tubular reactors. Heavily branched with branches of different lengths, crystallinity 40 to 50%, density 0.915 to 0.935 g / cm ³ , average molar mass up to 600000 g / mol.
• - PE-LLD (LLD = linear low density), available with metal comm plex catalysts in the low pressure process from the gas phase, from a solution (e.g. petrol), in a suspension or with a modified high pressure process. Weakly branched with in unbranched side chains, molecular weights higher than in LDPE.
• - PE-HD (HD = high density), available according to the medium pressure (Phillips) and low pressure (Ziegler) process. According to Phillips at 30 to 40 bar, 85 to 180 ° C, chromium oxide as a catalyst, molar masses about 50,000 g / mol. According to Ziegler at 1 to 50 bar, 20 to 150 ° C, titanium halides, titanium esters or aluminium malkyle as catalysts, molar mass about 200,000 to 400,000 g / mol. Carried out in suspension, solution, gas phase or mass. Very weakly branched, crystallinity 60 to 80%, density 0.942 to 0.965 g / cm ³ .
• - PE-HD-HMW (HMW = high molecular weight), available after Ziegler, Phillips or gas phase method. High density and high molecular weight.
• - PE-HD-UHMW (UHMW = ultra high molecular weight) available with modified Ziegler catalyst, molecular weight 3000000 bis 6000000 g / mol.

Polyethylene, which is in a gas phase vortex, is particularly suitable bed process using (usually supported) Catalysts is made, e.g. B. Lupolen® (Elenac).

Polyethylene is particularly preferred, which using Me tallocene catalysts is produced. Such polyethylene is z. B. commercially available as Luflexen® (Elenac).

Particularly suitable metallocene complexes are, for example DE-A 198 06 435, page 3, line 68 to page 5, line 67 be wrote. It is expressly referred to the passage mentioned grasslands. The synthesis of such complex compounds can be done according to known methods take place, the implementation of the ent accordingly substituted, cyclic hydrocarbon anions Halides of titanium, zirconium, hafnium, vanadium, niobium or Tantalum is preferred. Examples of corresponding manufacturing have proceeded u. a. in the Journal of Organometallic Chemistry, 369 (1989), 359-370.

Mixtures of different metallocene complexes can also be used be set.  

As a rule, the metallocene complexes are activated by an activator connection activated. Suitable activators are in particular Compounds that form metallocenium ions. Suitable metal Compounds forming ocenium ions are in particular complex ver bindings selected from the group of strong, neutral Lewis acids, the ionic compounds with Lewis acid cations and the ionic compounds with Bronsted acids as the cation. See Polypropylene below for details.

All commercially available ethylene copoly are ethylene copolymers suitable, for example Luflexen® types (Basell), Nordel® and Engage® (Dow, DuPont). All α-olefins are included as comonomers 3 to 10 carbon atoms suitable, in particular propylene, but-1-ene, Hex-1-ene and oct-1-ene, as well as alkyl acrylates and methacrylates with 1 to 20 carbon atoms in the alkyl radical, especially butyl acrylate. Other suitable comonomers are dienes such as. B. Butadiene, Iso pren and octadiene and dicyclopentadiene.

They are usually statistical copolymers or Block or impact copolymers.

Block or impact copolymers of ethylene and comonomers are Polymers in which a homopolymer of Comonomers or a random copolymer of the comonomer with up to 15 wt .-%, preferably up to 6 wt .-% ethylene and then in the second stage with a comonomer-ethylene copolymer Polymerized ethylene contents of 15 to 80 wt .-%. In the As a rule, so much of the comonomer-ethylene copolymer is added merized that the copolymer produced in the second stage in End product has a share of 3 to 60% by weight.

The polymerization to produce the ethylene comonomer copoly mere can be done using a Ziegler-Natta catalyst system Such catalyst systems are used in particular used in addition to a titanium-containing solid component Cocatalysts in the form of organic aluminum compounds and Have electron donor compounds.

However, catalyst systems based on metallo can also be used cen compounds or based on polymerization-active Metal complexes are used.

Propylene polymers

The term polypropylene is to be understood below to mean both homopolymers and copolymers of propylene. Copolymers of propylene contain minor amounts of monomers copolymerizable with propylene, for example C ₂ -C ₈ -alk-1-enes such as ethylene, but-1-ene, pent-1-ene or hex-1-ene. Two or more different comonomers can also be used.

Suitable polypropylenes include a. Homopolymers of propylene or Copolymers of propylene polymerized with up to 50% by weight other alk-1-enes with up to 8 carbon atoms. The copolymers of the Pro pylens are statistical copolymers or block or Im pactcopolymere. Provided the copolymers of propylene are statistical they generally contain up to 15% by weight, preferably up to 6% by weight, other alk-1-enes with up to 8 carbon atoms men, especially ethylene, but-1-ene or a mixture of ethylene and but-1-ene.

Block or impact copolymers of propylene are polymers in which, in the first stage, a propylene homopolymer or a statistical copolymer of propylene with up to 15% by weight, preferably up to 6% by weight, of other alk-1- ene with up to 8 carbon atoms and then in the second stage a propylene-ethylene copolymer with ethylene contents of 15 to 80 wt .-%, the propylene-ethylene copolymer additionally additional C ₄ -C ₈ - May contain alk-1-ene, polymerized. As a rule, so much of the propylene-ethylene copolymer is polymerized in that the copolymer produced in the second stage has a proportion of 3 to 60% by weight in the end product.

The polymerization for the production of polypropylene can be carried out using a Ziegler-Natta catalyst system. In doing so in particular those catalyst systems used in addition to a titanium-containing solid component a) or cocatalysts in the form of organic aluminum compounds b) and electron donor have connections c).

As titanium-containing solid component a) are u. a. Halides or Alcohols of trivalent or tetravalent titanium are suitable. suitable Aluminum compounds b) are in particular trialkyl aluminum compounds whose alkyl groups each have 1 to 8 carbon atoms have, for example trimethyl aluminum, triethyl aluminum, Tri-iso-butyl aluminum, trioctyl aluminum or methyl diethyl aluminum or mixtures thereof.

In addition to the aluminum compound b) is usually used as a further cocatalyst electron donor compounds c) such mono- or polyfunctional carboxylic acids, carboxylic anhydrides or carboxylic acid esters, furthermore ketones, ethers, alcohols, lactones, and organophosphorus and organosilicon compounds, the  Electron donor compounds c) the same or different from the to produce the titanium-containing solid component a) set electron donor compounds can be.

Instead of Ziegler-Natta catalyst systems, preferably on inorganic oxides or on polymers supported - metallocene compounds or polymerization-active Metal complexes can be used to manufacture polypropylene.

Suitable metallocene compounds are, for example
Ethylenebis (indenyl) zirconium dichloride,
Ethylenebis (tetrahydroindenyl) zirconium dichloride,
Diphenylmethylene-9-fluorenylcyclopentadienylzirkoniumdichlorid,
Dimethylsilanediylbis (-3-tert.butyl-5-methylcyclopentadienyl) zirconium dichloride,
Dimethylsilanediyl (2-methyl-4-azapentalen) (2-methyl-4 (4'-methylphenyl) -indenyl) zirconium dichloride,
Dimethylsilanediyl (2-methyl-4-thiapentalen) (2-ethyl-4 (4'-tert-butylphenyl) -indenyl) zirconium dichloride,
Ethanediyl (2-ethyl-4-azapentalen) (2-ethyl-4 (4'-tert-butylphenyl) indenyl) zirconium dichloride,
Dimethylsilanediylbis (2-methyl-4-azapentalene) zirconium dichloride,
Dimethylsilanediylbis (2-methyl-4-thiapentalene) zirconium dichloride,
Dimethylsilanediylbis (2-methylindenyl) zirconium dichloride,
Dimethylsilanediylbis (2-methylbenzindenyl) zirconium dichloride,
Dimethylsilanediylbis (-2-methyl-4-phenylindenyl) zirconium dichloride,
Dimethylsilanediylbis (-2-methyl-4-naphthylindenyl) zirconium dichloride,
Dimethylsilanediylbis (-2-methyl-4-isopropylindenyl) zirconium dichloride or
Dimethylsilanediylbis (-2-methyl-4,6-diisopropylindenyl) zirconium dichloride and the corresponding dimethylzirconium compounds.

The metallocene compounds are either known or according to known methods available. For catalysis too Mixtures of such metallocene compounds are used, furthermore the metallocene complexes described in EP-A 416 815.

The metallocene catalyst systems also contain metal Compounds forming ocenium ions. Strong, neutral ones are suitable Lewis acids, ionic compounds with Lewis acid cations or Ionic compounds with Bronsted acids as the cation. Examples are tris (pentafluorophenyl) borane, tetrakis (pentafluoro phenyl) borate or salts of N, N-dimethylanilinium. Also ge Suitable as compounds forming metallocenium ions are open chain or cyclic alumoxane compounds. These will  usually by reacting trialkyl aluminum with water produced and are usually different as mixtures long, both linear and cyclic chain molecules.

In addition, the metallocene catalyst systems can be metal organic compounds of the metals of I., II. or III. head Group of the periodic table contain such as n-butyl lithium, n-Bu tyl-n-octyl-magnesium or tri-iso-butyl aluminum, triethyl aluminum or trimethyl aluminum.

The polymerization to produce the polypropylenes used under normal reaction conditions at temperatures of 40 up to 120 ° C, in particular from 50 to 100 ° C and pressures from 10 to 100 bar, in particular from 20 to 50 bar.

Suitable polypropylenes generally have a melt flow rate (MFR), according to ISO 1133, from 0.1 to 200 g / 10 min. especially of 0.2 to 100 g / 10 min. at 230 ° C and under a weight of 2.16 kg.

4. Polyacrylates and polymethacrylates

These include in particular polymethyl methacrylate (PMMA) as well Copolymers based on methyl methacrylate with up to 40 wt .-% of other copolymerizable monomers to understand how for example under the names Lucryl® or Plexi glas® are available.

Homopolymers or copolymers based on are also suitable Acrylates such as B. butyl acrylate and possibly other comonomers. They are used, for example, as thermoplastic elastomers used.

5. Polyamides (PA)

Polyamides with aliphatic semi-crystalline or are suitable partly aromatic and amorphous structure of all kinds and their Blends, including polyether amides such as polyether block amides. Polyamides in the sense of the present invention should all known polyamides can be understood. Such polyamides have generally a viscosity number of 90 to 350, preferably 110 up to 240 ml / g determined in a 0.5 wt .-% solution in 96% by weight sulfuric acid at 25 ° C according to ISO 307.

Semi-crystalline or amorphous resins with a molecular weight (Weight average) of at least 5000, as z. Tie American patents 2,071,250, 2,071,251, 2,130,523,  2 130 948, 2 241 322, 2 312 966, 2 512 606 and 3 393 210 be are preferred. Examples include poly amides derived from lactams with 7 to 13 ring members, such as polycaprolactam, polycapryllactam and polylaurinlactam, and Polyamides made by reacting dicarboxylic acids with diamines be preserved.

As dicarboxylic acids are alkanedicarboxylic acids with 6 to 12 ins special 6 to 10 carbon atoms and aromatic dicarbon acids can be used. Here are adipic acid, azelaic acid, sebacin acid, dodecanedioic acid (= decanedicarboxylic acid) and terephthalic and / or called isophthalic acids. Are suitable as diamines especially alkane diamines with 6 to 12, in particular 6 to 8 carbons atoms of matter and m-xylylenediamine, di- (4-aminophenyl) methane, Di (4-aminocyclohexyl) methane, 2,2-di (4-aminophenyl) propane or 2,2-di- (4-aminocyclohexyl) propane.

Preferred polyamides are polyhexamethylene adipamide (PA 66) and polyhexamethylene sebacic acid amide (PA 610), polycaprolactam (PA 6) and copolyamides 6/66, in particular with a proportion of 5 to 95% by weight of caprolactam units. PA 6, PA 66 and Copolyamides 6/66 are particularly preferred.

In addition, polyamides should also be mentioned, which, for. B. by Condensation of 1,4-diaminobutane with adipic acid with increased Temperature are available (polyamide 4.6). production method for polyamides of this structure, e.g. B. in EP-A 38 094, EP-A 38 582 and EP-A 39 524. Other examples are Polyamides obtained by copolymerizing two or more of the aforementioned monomers are available, or mixtures of several Suitable polyamides, the mixing ratio is arbitrary.

Furthermore, such partially aromatic copolyamides as PA 6 / 6T and PA 66 / 6T proved to be particularly advantageous, their Triamine content less than 0.5, preferably less than 0.3% by weight (see EP-A 299 444). The manufacture of the semi-aromatic copolyamides with low triamine content can by the processes described in EP-A 129 195 and 129 196 respectively.

The following non-exhaustive list contains the ge, as well as other polyamides in the sense of the invention (the monomers are given in parentheses):
PA 46: (tetramethylene diamine, adipic acid)
PA 66: (hexamethylene diamine, adipic acid)
PA 69: (hexamethylenediamine, azelaic acid)
PA 610: (hexamethylenediamine, sebacic acid)
PA 612: (hexamethylene diamine, decanedicarboxylic acid)
PA 613: (hexamethylene diamine, undecanedicarboxylic acid)
PA 1212: (1,12-dodecanediamine, decanedicarboxylic acid)
PA 1313: (1,13-diaminotridecane, undecanedicarboxylic acid)
PA MXD6: (m-xylylenediamine, adipic acid)
PA TMDT: (trimethylhexamethylene diamine, terephthalic acid)
PA 4: (pyrrolidone)
PA 6: (ε-caprolactam)
PA 7: (ethanolactam)
PA 8: (caprylic lactam)
PA 9: (9-aminopelargonic acid)
PA 11: (11-aminoundecanoic acid)
PA 12: (laurolactam).

These polyamides and their production are known. details the specialist can find them in Ullmann's encyclopedia der Technischen Chemie, 4th edition, vol. 19, pp. 39-54, Verlag Che mie, Weinheim 1980, and Ullmann's Encyclopedia of Industrial Chemistry, Vol. A21, pp. 179-206, VCH Verlag, Weinheim 1992, and Stoeckhert, Kunststofflexikon, 8th edition, pp. 425-428, Hanser- Verlag Munich 1992 (keyword "polyamides" and the following).

Corresponding polyamides are available under the trade name Ultramid® from BASF available.

6. Vinyl aromatic polymers

The molecular weight of these known and commercially available polymers is generally in the range of 1500 to 2,000,000, preferably in the range of 7,000,000 to 1,000,000.

Vinyl aromatic polymers are only representative of this Styrene, chlorostyrene, alpha-methylstyrene and p-methylstyrene Nannt; Comonomers such as (meth) acrylonitrile or (Meth) acrylic acid esters to be involved in the construction. Especially before Preferred vinyl aromatic polymers are polystyrene, styrene-acrylic tril copolymers (SAN) and impact modified polystyrene (HIPS = High Impact Polystyrene) and styrene comonomer block co polymers, e.g. B. with butadiene (about two-block SB and three-block SBS), or ethylene-butylene (about three-block SEBS) as a comonomer. It is understood that mixtures of these polymers are also used can be. The production preferably takes place after the in of the methods described in EP-A-302 485.  

Furthermore, ASA, ABS and AES polymers (ASA = Acrylni tril-styrene-acrylic ester, ABS = acrylonitrile-butadiene-styrene, AES = Acrylonitrile-EPDM rubber styrene) is particularly preferred. This Impact-resistant vinyl aromatic polymers are described in more detail below described.

The impact-resistant vinyl aromatic polymers contain at least one rubber-elastic graft polymer A and a thermoplastic polymer B (matrix polymer). Graft polymers A which contain as rubber are preferably used:

• - a diene rubber based on dienes with conjugated Double bonds. Such services are e.g. B. butadiene, isoprene, Norbornene, and their halogen-substituted derivatives, for example Chloroprene. Butadiene and isoprene are preferred, especially butadiene.
• - An alkyl acrylate rubber based on alkyl esters of acrylic acid, in particular (C ₁ -C ₁₀ alkyl) esters of acrylic acid, such esters are e.g. B. ethyl acrylate, 2-ethylhexyl acrylate and n-butyl acrylate. 2-Ethylhexyl acrylate and n-butyl acrylate are preferred, n-butyl acrylate is very particularly preferred. The alkyl acrylate rubber is usually crosslinked, for which purpose crosslinking monomers are used, e.g. B. butadiene and isoprene, divinyl esters of dicarboxylic acids such as succinic acid and adipic acid, diallyl and divinyl ethers of bifunctional alcohols such as ethylene glycol and butane-1,4-diol, diesters of acrylic acid and methacrylic acid with the bifunctional alcohols mentioned, 1.4 -Divinyl benzene, triallyl cyanurate and - particularly preferably - the acrylic acid ester of tricyclodecenyl alcohol (see DE-OS 12 60 135), which is known under the name dihydrodicyclopenta dienyl acrylate, and the allyl esters of acrylic acid and methacrylic acid;
• - An EPDM rubber based on ethylene, propylene and a diene such as B. ethylidene norbornene and dicyclopentadiene.

The graft polymers A can also be mixtures of these rubbers or contain rubber monomers.

The rubber usually forms the basic stage of the graft poly mers. At the basic level, a or several graft stages polymerized, resulting in polymer particles with a rubber core and one or more grafts shells arise.  

The graft stage (s) usually contain at least one of the following monomers:
vinyl aromatic monomers such as styrene, styrene derivatives of the general formula

with n = 0, 1, 2 or 3, in which R ¹ and R ^{2 are} hydrogen or C ₁ - to C ₈ -alkyl;
Acrylonitrile, methacrylonitrile;
C ₁ - to C ₄ -alkyl esters of methacrylic acid, such as methyl methacrylate, also the glycidyl esters, glycidyl acrylate and methacrylate;
N-substituted maleimides such as N-methyl, N-phenyl and N-cyclo hexyl maleimide;
Acrylic acid, methacrylic acid, further dicarboxylic acids such as maleic acid, fumaric acid and itaconic acid and their anhydrides such as maleic anhydride;
Nitrogen-functional monomers such as dimethylaminoethyl acrylate, diethylaminoethyl acrylate, vinylimidazole, vinylpyrrolidone, vinyl caprolactam, vinylcarbazole, vinylaniline, acrylamide and methacrylamide;
aromatic and araliphatic esters of acrylic acid and methacrylic acid, such as phenyl acrylate, phenyl methacrylate, benzyl acrylate, benzyl methacrylate, 2-phenylethyl acrylate, 2-phenylethyl methacrylate, 2-phenoxyethyl acrylate and 2-phenoxyethyl methacrylate;
unsaturated ethers such as vinyl methyl ether,
as well as mixtures of these monomers.

Preferred graft monomers are styrene, acrylonitrile, methyl meth acrylate, glycidyl acrylate and methacrylate, acrylamide and meth acrylamide.

The graft shell is preferably composed of polymers such as them below as preferred embodiments B / 1 to B / 4 of Matrix polymers B can be called.

The graft polymers A can be prepared in various ways Be carried out way, especially in emulsion, in micro emulsion, in mini emulsion, in suspension, in microsuspension, in Mini suspension, as precipitation polymerization, in bulk or in Solution or as a combination of two methods such. B. mass /  Solution, solution / precipitation, mass / suspension and mass / emulsion. a Details of the polymerization processes mentioned and the required auxiliaries such as emulsifiers, initiators, etc. see for example DE-A 197 52 394.

Furthermore, the impact-resistant vinyl aromatic polymers contain at least one thermoplastic polymer B (matrix polymer). Component B preferably has a glass transition temperature T _g of 50 ° C. or above. B is therefore a hard polymer.

Preferred components B are, for example, polystyrene and Copolymers of styrene and / or alpha-methylstyrene and one or several of the monomers methyl methacrylate, N-phenylmaleimide, Maleic anhydride and acrylonitrile, particularly preferably methyl methacrylate and acrylonitrile.

Examples of preferred components B are:
B / 1: polystyrene
B / 2: copolymer of styrene and acrylonitrile,
B / 3: copolymer of alpha-methylstyrene and acrylonitrile,
B / 4: copolymer of styrene and methyl methacrylate.

The proportion of styrene or alpha-Me is particularly preferred thylstyrene or the proportion of the sum of styrene and alpha-Me thylstyrene at least 40 wt .-%, based on component B.

Component B can be prepared in a manner known per se, e.g. B. by Substance, solution, suspension, precipitation or emulsion poly receive merisation. Details of these procedures are e.g. B. in Plastic handbook, ed. Vieweg and Daumiller, Carl-Hanser-Verlag Munich, Vol. 1 (1973), pp. 37 to 42 and Vol. 5 (1969), pp. 118 to 130, as well as in Ullmann's encyclopedia of technical chemistry, 4th edition, Verlag Chemie Weinheim, vol. 19, pp. 107 to 158 "Polyme rization technology ".

Usually the impact-resistant contain vinyl aromatic Polymers 5 to 80, preferably 10 to 70 and particularly preferably 15 up to 60% by weight of the rubber-elastic graft polymer A and corresponding to 20 to 95, preferably 30 to 90 and especially before adds 40 to 85% by weight of the thermoplastic polymer B.

The styrene-comonomer block copolymers already mentioned include also three-block copolymers styrene-butadiene-styrene (SBS) and styrene Ethylene butylene styrene (SEBS). They usually become the  attributed to thermoplastic elastomers, see here under No. 10.

7. Polyarylene ether

Polyarylene ethers are preferably both polyarylene ethers per se, polyarylene ether sulfides, polyarylene ether sulfones or poly arylene ether ketones. Their arylene groups can be the same or different and independently of one another represent an aromatic radical having 6 to 18 carbon atoms. Examples of suitable arylene radicals are phenylene, bisphenylene, terphenylene, 1,5-naphthylene, 1,6-naphthylene, 1,5-anthrylene, 9,10-anthrylene or 2,6-anthrylene. Among them, 1,4-phenylene and 4,4'-biphenylene are preferred. These aromatic radicals are preferably not substituted. However, you can carry one or more substituents. Suitable substituents are, for example, alkyl, arylalkyl, aryl, nitro, cyano or alkoxy groups, such as heteroaromatics such as pyridine and halogen atoms. The preferred substituents include alkyl radicals with up to 10 carbon atoms such as methyl, ethyl, i-propyl, n-hexyl, i-hexyl, C ₁ - to C ₁₀ -alkoxy radicals such as methoxy, ethoxy, n-propoxy, n-butoxy , Aryl residues with up to 20 carbon atoms such as phenyl or naphthyl as well as fluorine and chlorine. In addition to -O-, e.g. B. over -SS-, -SO-, -SO ₂ -, -CO-, -N = N-, -COO-, an alkylene radical or a chemical mixture bond. In the polyarylene ethers, the arylene groups can also be linked to one another via different groups.

The preferred polyarylene ethers include those with recurring units of the general formula

Their core-substituted derivatives can also be used. Possible substituents are preferably C ₁ -C ₆ -alkyl, such as methyl, ethyl or t-butyl, C ₁ -C ₆ -alkoxy, such as methoxy or ethoxy, aryl, in particular phenyl, chlorine or fluorine. The variable X can be -SO ₂ -, -SO-, -S-, -O-, CO, -N = N-, -RC = CR ^a -, -CR ^b R ^c - or a chemical bond. The variable Z can stand for -SO ₂ -, -SO-, -CO-, -O-, -N = N- or -RC = CR ^a . Here, R and R ^a each represent hydrogen, C ₁ -C ₆ alkyl, e.g. As methyl, n-propyl or n-hexyl, C ₁ -C ₆ alkoxy, including methoxy, ethoxy or butoxy or aryl, especially phenyl. The radicals R ^b and R ^c can each be hydrogen or a C ₁ - to C ₆ alkyl group, in particular methyl. However, they can also be linked together to form a C ₄ to C ₁₀ cycloalkyl ring, preferably cyclopentyl or cyclohexyl ring, which in turn can be substituted by one or more alkyl groups, preferably methyl. In addition, R ^b and R ^{c can} also be a C ₁ - to C ₆ -alkoxy group, e.g. B. methoxy or ethoxy or an aryl group, especially phenyl. The groups mentioned above can each be substituted with chlorine or fluorine.

The polyarylene ethers can also be copolymers or block copolymers, in those of polyarylene ether segments and segments from others thermoplastic polymers such as polyamides, polyesters, aromati rule polycarbonates, polyester carbonates, polysiloxanes, poly imides or polyetherimides are present. The molecular weights of the Blocks or the graft arms are generally in the copolymers in the range of 1000 to 30000 g / mol.

In general, the polyarylene ethers have medium molecular weight weight Mn (number average) in the range from 10,000 to 60,000 g / mol and viscosity numbers from 30 to 150 ml / g. The viscosity numbers are either in depending on the solubility of the polyarylene ether 1% by weight N-methylpyrrolidone solution, in mixtures of phenol and o-dichlorobenzene or in 96% sulfuric acid in each case 20 ° C or 25 ° C measured.

The polyarylene ethers are known per se or can per se known methods are produced.

Preferred process conditions for the synthesis of polyarylene ether sulfones or ketones are for example in the EP-A-113 112 and EP-A 135 130.

The preferred polyarylene ethers usually have one Melting point of at least 320 ° C (polyarylene ether sulfones) or of at least 370 ° C (polyarylene ether ketones).

8. Polyurethanes, polyisocyanurates and polyureas

Soft, semi-hard or hard, thermoplastic or cross-linked bottom lyisocyanate polyadducts, for example polyurethanes, Polyisocyanurates and / or polyureas, especially polyures thane, are well known. Their manufacture is diverse and is usually carried out by implementing (a) Isocyanates with (b) isocyanate-reactive compounds under generally known conditions. The implementation is preferred in the presence of (c) catalysts and / or (d) auxiliaries  carried out. If it is foamed polyisocyanate polyaddi tion products, they are in the presence of usual Propellant (s) produced.

As isocyanates (a) come the known aromatic, arylaliphatic, aliphatic and / or cycloaliphatic or ganic isocyanates, preferably diisocyanates.

As compounds (b) reactive toward isocyanates for example, well-known compounds with one molecule lar weight from 60 to 10000 and a functionality compared Isocyanates of 1 to 8, preferably 2 to 6 are used (in Case of thermoplastic polyurethane TPU functionality approx. 2), for example polyols with a molecular weight of 500 to 10,000, e.g. B. polyether polyols, polyester polyols, polyether poly ester polyols, and / or diols, triols and / or polyols with molecule Lar weights less than 500.

As catalysts (c) for the preparation of the products can be given if necessary, generally known compounds are used, wel the reaction of isocyanates with those against isocyanates accelerate reactive compounds strongly, preferably a total catalyst content of 0.001 to 15 wt .-%, in particular 0.05 to 6 wt .-%, based on the weight of the total set compounds (b) reactive towards isocyanates, is used, for example tertiary amines and / or metal salts, for example inorganic and / or organic Compounds of iron, lead, zinc, and / or tin in usual Oxidation levels of the metal.

Customary substances can optionally be used as auxiliary substances (d) be used. Examples include surface-active ones Substances, fillers, dyes, pigments, flame retardants, Hydrolysis protection, we fungistatic and bacteriostatic substances, UV stabilizers and antioxidants.

Details on polyurethanes, polyisocyanurates and polyurea the specialist can find substances in the plastic manual, 3rd edition, Volume 7 "Polyurethane", Hanser-Verlag, Munich 1993.

9. Polylactide

Polylactides, that is to say polymers of lactic acid, are known per se or can be prepared by processes known per se. In addition to polylactide, copolymers or block copolymers based on lactic acid and other monomers can also be used. Linear polylactides are mostly used. However, branched lactic acid polymers can also be used. As branching z. B. serve multifunctional acids or alcohols. Examples include polylactides, which consist essentially of lactic acid or its C ₁ - to C ₄ -alkyl esters or mixtures thereof, as well as at least one aliphatic C ₄ - to C ₁₀ -dicarboxylic acid and at least one C ₃ - to C ₁₀ -alkanol with three up to five hydroxy groups are available.

10.Thermoplastic elastomers (TPE)

Thermoplastic elastomers (TPE) can be like thermoplastics process, but have rubber-elastic properties. It are TPE block polymers, TPE graft polymers and segmented TPE Copolymers of two or more monomer units are suitable. Beson Suitable TPE are thermoplastic polyurethane elastomers (TPE-U or TPU), styrene-oligoblock copolymers (TPE-S) such as SB (Styrene-butadiene block copolymer), SBS (styrene-butadiene-styrene Block copolymer) and SEBS (styrene-ethylene-butylene-styrene block co polymer, obtainable by hydrogenating SBS), thermoplastic Polyolefin elastomers (TPE-O), thermoplastic polyester elasto mere (TPE-E), thermoplastic polyamide elastomers (TPE-A) and especially thermoplastic vulcanizates (TPE-V). The latter ent hold z. B. a thermoplastic and vul to a small extent canned rubber. A blend is an example of TPE-V Polypropylene and low vulcanized EPDM (ethylene propylene Diene rubber).

Those skilled in the art will find details on TPE in G. Holden et al., Thermoplastic Elastomers, 2nd edition, Hanser-Verlag, Munich 1996th

11. Halogen-containing polymers

Polymers of vinyl chloride are particularly worth mentioning here. especially polyvinyl chloride (PVC) such as hard PVC and soft PVC, and copolymers of vinyl chloride such as PVC-U molding compounds.

Fluorine-containing polymers are also suitable, in particular Polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoropropylene Copolymers (FEP), copolymers of tetrafluoroethylene with perfluoro alkyl vinyl ether, ethylene tetrafluoroethylene copolymers (ETFE) poly vinylidene fluoride (PVDF), polyvinyl fluoride (PVF), polychlorotri fluoroethylene (PCTFE), and ethylene-chlorotrifluoroethylene copolymers (ECTFE).  

12. Imide group-containing polymers

Polymers containing imide groups are in particular polyimides, poly etherimide and polyamideimide.

13. Cellulose ester

Suitable cellulose esters include cellulose acetate and cellulose acetobutyrate, and cellulose propionate.

14. Silicone polymers

Silicone rubbers are particularly suitable. This is what it is about are usually polyorganosiloxanes that cause crosslinking craze have capable groups. Such polymers are for example in Römpp Chemie Lexikon, CD-ROM version 1.0, Thieme-Verlag Stuttgart 1995, under the keyword "Silicone" be wrote.

In addition to the polymers mentioned under Nos. 1 to 14, can also other polymers A are used, such as z. B. in the beginning described books by Saechtling or Becker and Braun be.

The surface active substance S

Emulsifiers in particular come as surface-active substance S. and protective colloids.

All common emulsifiers can be used. Which one Emulsifier is most suitable for a particular polymer A, results in a known manner from the chemical structure of the Additives (including polar / non-polar, hydrophilic / hydrophobic) and the Po lymeren and, if necessary, can be easily determine search.

Suitable emulsifiers are selected, for example, from the following the groups: alkali metal salts of alkyl or alkylarylsulfone acids (alkyl sulfonates or aralkyl sulfonates, especially alkyl benzenesulfonates), alkali metal salts of higher fatty acids with 10 to 30 carbon atoms, alkyl sulfates, fatty alcohol sulfonates, sulfosuccinates (especially alkyl sulfosuccinates), ether sulfonates, resin soaps, Fatty alcohol alkoxylates (especially fatty alcohol ethoxylates), fet talc polyglycol ethers, fatty acid ethoxylates, fatty acid polyglyco lether, tallow fatty alcohol oxyethylates, triethanolamine fatty acid esters, Block copolymers of ethylene oxide and propylene oxide, alkylaryl  polyglycol esters and alkylaryl polyglycol ethers. Fatty acid or Fatty alcohol means 10 to 30 carbon atoms.

The sodium, potassium or ammonium salts of long-chain fatty acids having 10 to 20 carbon atoms, salts of diproportioned abietic acid, salts of long-chain benzene sulfonates, salts of long-chain alkyl sulfonic acids, for. B. the sodium salts of C ₉ -C ₁₈ alkyl sulfonic acid mixtures, and salts of dicarboxylic acids based on cyclic hydrocarbon skeletons GE according to DE-A 36 39 904 and DE-A 39 13 509.

Suitable anionic emulsifiers are e.g. B. Dodecylbenzenesulfone acid salts, dodecyl sulfate salts, lauryl sulfate salts, dialkyl sulfo succinate salts, polyoxyethylene alkylphenyl ether sulfonic acid salts, and polyoxyethylene alkyl propenylphenyl ether sulfonic acid salts, white also formaldehyde condensates of naphthalenesulfonic acid. salt means in particular sodium, potassium or ammonium salt.

Suitable nonionic emulsifiers are e.g. B. Polyoxyethylene no nylphenyl ether, polyethylene glycol monostearate, polyoxyethyleneal kylpropenylphenyl ether, and sorbitan monostearate. Also reactive Emulsifiers such as sodium naphthalene sulfonate can be used the.

Other suitable emulsifiers are resin acid potassium salt and Na trium salt, sodium palmitate, sodium oleate, sodium dodecylbenzene sulfonate, sodium palmityl sulfonate and sodium dioctyl sulfosucci nat, or the corresponding potassium and ammonium compounds.

Other suitable emulsifiers are, for example, the books from H. Stache and K. Kosswig, Tensid-Taschenbuch, 3rd edition, Hanser- Verlag München, 1990, as well as K. Kosswig and H. Stache; The ten side, Hanser-Verlag Munich, 1993.

Montan waxes, i.e. bitumen from lignite, are also well suited. They usually have at least one of the following properties: density 1.02-1.03 g / cm ³ , melting point 80-84 ° C, saponification number 62-70, unsaponifiable fraction 25-35%, acid number up to 300, ash 0.3-0.4%. Montan waxes usually consist of approx. 53% esters of C ₂₂ to C ₃₄ fatty acids (mainly hexacosanoic, octacosanoic and triacontanoic acids) with C ₂₄ , C ₂₆ and C ₂₆ wax alcohols. Other components are free fatty acids (approx. 17%) and free wax alcohols (approx. 1-2%) as well as montan resins (approx. 15-25%), ketones and asphalt-like material. The percentages are approximate values.

The following emulsifiers are particularly suitable: montan waxes, Potassium stearate, sodium stearate, potassium oleate, potassium palmitate, as well the alkyl sulfonates, sulfosuccinic acid esters, alkyl sulfo succinates, fatty alcohol alkoxylates, alkylbenzenesulfonates, fatty acids reethoxylates, fatty acid polyglycol ethers, alkylaryl polyglycol esters and alkylaryl polyglycol ether.

The compounds known to the person skilled in the art come as protective colloids into consideration. Suitable protective colloids are e.g. B. cellulose derivatives such as carboxymethyl cellulose and hydroxymethyl cellulose, poly-N-Vi nylpyrrolidone, polyvinyl alcohol and polyethylene oxide, anionic Polymers such as polyacrylic acid and their copolymers and cationic such as poly-N-vinylimidazole.

Protective colloids and methods for producing protection colloids are known per se and, for example, in Encyclopedia of Polymer Science and Engineering, Vol. 16, p. 448, Verlag John Wiley, 1989.

One or more polyvinyl alcohols are preferred as protection colloid used, especially those with a degree of hydrolysis below 96 mol%, particularly preferably 60 to 94 and very particularly preferably 65 to 92 mol%. The preferred polyvinyl alcohols ha ben a viscosity of 2 to 100 mPa.s, in particular from 4 to 60 mPa.s, measured as a 4% by weight solution in water at 20 ° C DIN 53 015.

Of course, mixtures of several surfaces can also be used active substances S can be used. So you can z. B. several Emulsifiers, or several protective colloids, or emulsifiers and Use protective colloids together.

In addition to surfactants, other auxiliaries substances are used which, for. B. mixing the polymer with facilitate the water, improve the dispersion or the Stabilize polymer dispersion. Suitable auxiliaries are ins special bases such as alkali metal hydroxide, e.g. B. KOH, NaOH, or Compounds containing amino groups, such as triethanolamine. to suitable auxiliaries are z. B. substances with acidic and / or buffering properties.

The surface-active substances S and / or the auxiliary substances can as such, or dissolved or dispersed in a solution or dispersing agents, especially water, into the extruder be dosed. For example, the substances S and / or the excipients or part of S or the excipients in the  Dissolve or disperse water that is present in the mixing zones in Ex truder is metered.

The procedure

According to the invention, the polymer A, the surface-active substance S and the water are mixed in a twin-screw extruder. The speed of the extruder screws is at least 600 min ^-1 . It is therefore a high-speed extruder, in contrast to the prior art cited at the beginning DE-A 41 15 531, which discloses 250 min ^-1 .

A meshing twin-screw extruder is preferably used.

The upper limit of the screw speed should be chosen so that the polymer A is not unnecessarily thermally damaged by the friction energy introduced (friction heat), on the other hand it is sufficiently dispersed in the aqueous phase. The upper speed limit depends, inter alia, on the polymer to be dispersed and can generally be up to 3000, preferably up to 2000 and particularly preferably up to 1200 min ^-1 .

In a preferred embodiment, the speed of the extruder screws is at least 700 min ^-1 .

In another, also preferred embodiment, rotate the extruder screws in the same direction.

According to the invention, the extruder is viewed in the conveying direction built up from a feed zone, a melting zone, a first one and last mixing zone and a discharge zone. The as zones or Parts of the extruder designated sections are not necessarily identical to the individual extruder components len such as housing parts, screw segments, etc. A section or a zone usually consists of several components.

In the feed zone (feed zone), polymer A is fed into the extruder metered. That is why the feed zone is also used as a metering section or zone.

Polymer A is usually in the form of a solid powder, granules, Semolina, scales, grains or any other lumpy form; a previous melting is usually not necessary. Polymer A is fed to the feed zone of the extruder. The feed zone an automatically operating dosing is usually assigned device and the actual metering opening. The dosing device is designed for example as a screw conveyor,  which conveys or pushes the material to be conveyed into the metering opening. It is also possible to use polymer A by suitable gravimetric or dosing volumetric dosing devices and in free fall in insert the feed opening of the extruder. By means of an egg gneten screw geometry in the metering section is achieved that component A is drawn in and vented.

In one possible embodiment there is a vent tion zone upstream against the direction of extrusion ders. It typically has one or more vents openings through which trapped air can escape.

In another preferred embodiment, the dosage opening of the metering section or into one or more, openings on the metering section, the surface-active Substance S, or proportions of the total amount of sub punch S, dosed. This can also be done in another, optional existing feed zone that follow the first feed zone can.

Substance S can be separated from polymer A or in the feed zone are fed together with A to the extruder, a previously It is usually not necessary to mix A with S.

The metering device for substance S can be mentioned in both Embodiments depending on the physical state of S for example a screw conveyor as in the metering of polymer A, a Pump or an extruder.

The above three paragraphs apply mutatis mutandis to others Auxiliaries such as alkali metal hydroxide or the others mentioned Excipients.

In the area of the feed zone and - if available - the ventilation zone, the extruder screws are usually used as a normal conveyor trained snails. Usual screw conveyors in the sense of the Er are z. B. Elements with "Erdmenger" profile (complete self-cleaning), sliding edge elements, elements with trapezoidal profile and elements with a rectangular profile, or a combination of these elements mente.

The temperature in the feed zone is preferably selected such that the polymer is easily drawn in, but not yet melts. A temperature of 10 to 150, ins is preferred particularly 20 to 100 ° C below the melting point (softening point) of polymer A adjusted.  

The polymer A metered in the feed zone becomes downstream in promote the melting zone in which it is melted.

The melting zone is preferably with plasticizing elements Mistake. The plasticizing elements melt the polymer A. on. If several polymers A have been metered into the feed zone, the plasticizing elements also serve to homogenize the Polymer mixture.

The plasticizing elements are familiar to those skilled in the art Components into consideration, for example mixing, kneading and stuck snail elements. Suitable mixing or kneading elements are z. B. elements with a slight slope in the conveying direction, kneading blocks with narrow or wide, promotional or non-promotional Kneading disks, screw elements with a slope against the Conveying direction (so-called return screw elements), or a Combination of such elements.

Suitable storage elements are e.g. B. exaggerated, promotional Screw elements, screw elements with a slope opposite to the Direction of conveying, kneading blocks with non - conveying kneading disks in different widths, kneading blocks with returning incline, Kneading blocks with a promotional gradient, cylindrical discs, eccentric discs and blocks configured from them, neutral baffle plates ("Throttle plates"), mechanically adjustable throttles (sliding housings, radial chokes, central chokes), or a combination of these elements.

Usually a combination of mixing / kneading is used elements and damming elements.

The selection of the plasticizing elements in the melting zone with regard to their type, number and dimensions u. a. for polymer A, especially for viscosity and Er softening temperature, as well as after polymer mixing Miscibility of the components.

It is essential to the invention that the extruder screws are made in this way stalten are that in the extruder between the melting zone and the subsequent first mixing zone (for the mixing zone see white ter below) forms a ring of melted polymer A, which seals the subsequent extruder contents towards the feed zone. the This so-called melting ring fills the space between the extruders screw and extruder housing and lies in a ring around the Slug. It resists the pressure of the extruder contents and prevents changes that the extruder content is pushed out in the feed zone.  

The screw elements are therefore in a manner known per se and depending on the operating conditions, that between the melting zone and the subsequent first Mixing zone creates a sealing melting ring. As operating Examples are: conditions, throughput, type, quantity, Softening point and viscosity of polymer A, screw rotation number, temperature in the individual extruder zones, quantity and Temperature of the metered water, etc.

The extruder can one or after the melting zone described contain several further melting zones, for example if melting the polymer or homogenizing the Polymer mixture incomplete in the first melting zone was.

The surface-active substance S, or parts of the total amount of S added, for example by means of a metering opening and a metering device direction (pump, side extruder, or similar).

The temperature in the melting zone is preferably so high chooses the polymer to go into the molten state. On the other hand, the temperature should not be higher than required Lich to minimize the thermal damage to the polymers. The suitable temperature depends on the polymer in a known manner and can be determined by simple preliminary tests if necessary.

The polymer melted in the melting zone becomes downstream into the first mixing zone, where part of the what is metered in and mixed with the polymer melt. The The mixing zone is therefore a water metering zone.

The first mixing zone usually contains mixing elements or Kneading elements or both. These elements have been previously wrote. This embodiment is preferred.

The mixing zone can also contain damming elements; in many cases however, no baffle elements are required. The mixing, kneading and, if necessary, baffle elements mix the polymer melt with the dosed water.

The mixing, kneading and optionally baffle elements are preferably also used for Delimitation of the first mixing zone from the previous melting zone and / or the subsequent mixing zone.  

The water is fed in through one or more metering openings dosed. Common dosing devices are used for this, for example pumps. Water dosing takes place over several A single opening in some cases makes vermi easier water with the polymer.

Because the temperature of the extruder content is usually higher than you is the point of the water, the metering openings are operated preferably under excess pressure to prevent evaporation of the water prevent. The pressure is preferably set so that it Vapor pressure of the extruder content, i.e. the polymer-water mixture sches, corresponds.

The temperature of the water metered into the first mixing zone is generally from 10 to below 100, preferably from 20 to 90 and especially 22 to 80 ° C. However, you can also take the water under Add pressure at temperatures of 100 ° C or above.

The temperature in the first mixing zone is preferably so high chooses that the polymer remain in the molten state. The metered water should therefore not solidify the polymer sen. On the other hand, the temperature should not be higher than him required to minimize the thermal damage to the polymers and a possible chemical reaction of the polymer with water (e.g. hydrolysis). The set Temperature also affects the viscosities of poly mer (melt) and water and the important for the dispersion Difference in viscosity between polymer and water. Prefers becomes a temperature of 10 to 150, in particular 15 to 120 ° C. above the melting point (softening point) of polymer A. provides. Preferred upper temperature limit is 350, in particular 340 ° C, depending on the polymer.

The amount of water metered into the first mixing zone is preferably less than 20, in particular less than 50 and particularly preferably less than 95% by weight of the total amount of water, which is metered into the extruder. The latter is identical to the total amount of water that ent in the finished polymer dispersion hold is.

There is probably a mixture of water in the first mixing zone in polymer before (water as disperse phase, no phases yet inversion).

In the first mixing zone, the surface-active substance S, or part of the total amount of S, can be added. This can done together with the metered water. For example  you can depending on the solubility of substance S in water a solution or dispersion (suspension or emulsion) of S in water dosing. However, substance S can also be separated from what inflict it.

The preceding paragraph applies mutatis mutandis to further help substances such as alkali metal hydroxide, or the others mentioned Excipients.

The polymer-water mixture obtained in the first mixing zone is conveyed downstream into the last mixing zone in which the remaining part of the water metered in and with the polymer water Mixture is mixed. The last mixing zone is therefore flat if a water metering zone.

With regard to the screw elements, the metering openings and the Pressure of the water metering apply to the above explanations for the first mixing zone. The structure and the operation conditions of the first and last mixing zone identical or ver be divorced. In particular, the type, length and arrangement of the Screw elements in the last mixing zone may be different from the first mixing zone.

The last mixing zone usually also contains mixing elements or kneading elements or both. These elements were previously already described. This embodiment is preferred.

The mixing zone can also contain damming elements; in many cases however, no baffle elements are required. The mixing, kneading and possibly damming elements mix the polymer-water mixture with the metered water, and are also used for demarcation the last mixing zone to the previous first mixing zone and / or the subsequent discharge zone.

The last mixing zone is preferably designed so that it is the Extruder content mixed more than the first mixing zone. To can, if necessary, in the last mixing zone, for example Use more shear or longer screw elements than in the first.

The temperature of the metered water in the last mixing zone is usually 10 to 340, preferably 20 to 300 and ins particularly 20 to 200 ° C. It follows that the water falls is metered in under excess pressure.  

The temperature in the last mixing zone is preferably so high chosen so that the polymer remains in the molten state. The metered water should therefore not solidify the polymer sen. On the other hand, the temperature should not be higher than him required to minimize the thermal damage to the polymers and a possible chemical reaction of the polymer with water (e.g. hydrolysis). The set Temperature also affects the viscosities of poly mer (melt) and water and the important for the dispersion Difference in viscosity between polymer and water. Prefers a temperature of 10 to 150, in particular 1 to 120 ° C above the melting point (softening point) of polymer A. The preferred upper temperature limit is 350, in particular 340 ° C., from dependent on the polymer.

The amount of water metered in the last mixing zone is preferably at least 20, in particular at least 50 and especially preferably at least 95% by weight of the total amount of water contained in the extruder is metered. The latter is identical to the Ge total amount of water contained in the finished polymer dispersion is.

The final water content (solid substance content) of the polymer dispersion. An afterthought ches dilution of the dispersion prepared to the desired Solids content is eliminated. This is an essential difference on the prior art cited at the beginning of EP-A 246 729 and DE-A 41 15 531.

The final solids content of the polymer dispersion is 5 to 95, preferably 20 to 90 and particularly preferably 30 to 70% by weight, based on the dispersion.

At the end of the last mixing zone there is probably a mixture of Polymer in water before (polymer as disperse phase), so it has probably phase inversion has occurred. It is clear that the Ex a polymer-in-water dispersion in the discharge zone leaves.

As in the first mixing zone, the last one can Mixing zone the surface-active substance S, or part of the Total amount of S or the auxiliary substances are metered in. in the special one can add S dissolved or dispersed in the water gene, which is metered into the extruder. The same applies to the optional auxiliaries already mentioned, such as alkali metal  hydroxide or the other excipients mentioned. In detail the above applies.

Additional auxiliaries can also be used in the last mixing zone are metered in, which, for. B. the stability, shelf life or Affect application properties of the polymer dispersion, e.g. B. Fungicides, bactericides, fragrances, deodorants, etc.

According to the invention, the extruder contains two mixing zones; the total The amount of water is therefore distributed over two mixing zones. However, det in a very particularly preferred embodiment between another mixing zone between the first and the last mixing zone zone in which part of the water is metered in and mixed with the polymer Water mixture is mixed. In this embodiment the total amount of water is distributed over three mixing zones.

With regard to the screw elements, the metering openings, the Pressure of the water metering, and the temperature of the metered The above explanations apply to water for the further mixing zone for the first or last mixing zone. Structure (screw elements) and operating conditions of the other mixing zone can differ from that most and last mixing zone.

What was metered in the further and in the last mixing zone The total amount is preferably at least 20, ins particularly at least 50 and particularly preferably at least 80% by weight of the total amount of water metered into the extruder becomes. The latter is identical to the total amount of water in the finished polymer dispersion is included.

Just like in the first and last mixing zone, the another mixing zone, the surface-active substance S, or Part of the total amount of S, can be added. The above applies what has been said.

As mentioned, the embodiment with three mixing zones is quite be particularly preferred. The amount of water in the further (middle) mixing zone is metered, is preferably 0.2 to 5 times the water metered in the previous first zone quantity. The amount of water that doses in the last mixing zone is preferably 3 to 20 times that in the previous dosed amount of water in the middle mixing zone.

The extruder can be in front of the last mixing zone, in which the end valid solids content of the polymer dispersion is set, also contain more than one other mixing zone in the water is metered in, for example a total of four or five mixes  zones. The above information also applies to this additional Mixing zone (s).

From what has been said it follows that the surface-active substance S in the feed zone, the melting zone, the first or the last one ten or the intermediate mixing zone or in meh reren these zones of the extruder can be metered.

In a preferred embodiment, the extruder screws designed so that the melting zone from the first mixing zone each connected with promotional elements and by return elements are delimited from each other. In another Embodiment are also the mixing zones from each other through such elements connected or delimited.

The polymer-water mixture obtained in the last mixing zone is conveyed downstream into the discharge zone in which the poly mer-water mixture is discharged.

The discharge zone is the last extruder section and consists of an extruder screw and a closed housing part, the is completed with a discharge opening. The snail is usually a conventional screw conveyor, as described above has already been described.

According to the discharge zone contains a pressure maintaining device tung. By means of the pressure holding device, the extruder content is relaxed to the ambient pressure (mostly atmospheric pressure). The Pressure maintenance device makes the complex cooling of the extruder content to a temperature below the boiling point of the water superfluous; It thus avoids the disadvantage of the beginning EP-A 972 794 and EP-A 246 729 cited prior art.

Suitable pressure-maintaining devices are, for example, taps or Valves (especially pressure maintenance valves), still pressure maintenance boiler.

Preferably, one operates the pressure maintaining device in such a way that the pressure loss occurring along the pressure maintaining device Vapor pressure of the polymer-water mixture corresponds to that exhausted will. For example, a tap or a valve as pressure holding device used, so you turn it or it exactly like this wide on that the tap or the valve the pressure of the extruder just hold still. The pressure loss is usually in the Range from 1 to 150, preferably 4 to 40 bar.  

A valve or another is preferred as the discharge opening pressure-maintaining opening through which the polymer dispersion flows out, d. H. Discharge opening and pressure maintenance device are identical.

The temperature in the discharge zone is preferably selected such that that the polymer melted in the previous zones again stiffens. However, it is not necessary to change the temperature in the Set discharge zone below the boiling point of the water. A temperature of 0.1 to 30, in particular 0.1, is preferred up to 20 ° C below the melting point (softening point) of polymer A set.

As is well known, the different zones can be one Extruders can be individually heated or cooled to run along to set an optimal temperature profile for the screw axis. It is also known to the person skilled in the art that usually the one individual sections of the extruder can be of different lengths.

The temperatures and lengths to be selected in individual cases individual extruder zones differ depending on the surface mix and physical properties of polymer A and surface-active substance S and their proportions. Sol che properties are z. B. the viscosities of the melt of Po lymer A and water, the softening temperatures of the components ten, their thermal resilience or tendency to decompose higher temperatures, their tendency to react with water (e.g. Resistance to hydrolysis), the compatibility in the sense of a Miscibility or wettability of components A, S and water, the residual water content of the metered polymer A, and in the case of particulate constituents, their particle size and Particle size distribution. Those mentioned in the individual zones Temperatures are e.g. B. in the usual way by heating or Cooling the corresponding extruder components (e.g. housing, Schnec ken) is set.

The total length of the extruder is in a preferred Aus leadership form 12 to 70, in particular 15 to 65 and very particularly preferably 16 to 60 D, where D is the screw diameter.

It is advantageous to design and operate the extruder such that, at a screw speed of 600 to 1200 min ^-1 , average shear rates of 100 to 1500, in particular 120 to 1000 s ^-1, set in the mixing zones. However, depending on the type, amount and properties of the components used, it may be expedient to work at medium shear rates outside of this range.

Depending on the type and quantity of the components, screws with a small flight depth or screws with a large flight depth (so-called "deep-cut screws") can be used in the extruder. Screws with a flight depth ratio of D _{screw outside} / D _{screw inside} of 1.1 to 1.8 are preferably used.

The number of flights of the snail can vary. Two are preferred common and / or three-course snails used. However, can snails with different numbers of threads are also used, or such snails, the sections with different numbers of gears exhibit.

With the method according to the invention, polymer dispersions are possible hältlich. They are also the subject of the invention.

The average particle size of the polymer particles in the dispersion varies depending on the type and amount of polymer A used, the surface-active substances and, if appropriate, the auxiliaries, and naturally depends on the design of the extruder. The average particle size D ₅₀ is usually in the range from 0.1 to 150, in particular 0.2 to 120 and particularly preferably 0.5 to 100 micrometers.

The average particle size D is the volume average of the particle size, as z. B. be true by means of light scattering. You can do this e.g. B. Malvern devices are ver. The volume-average particle diameter D ₅₀ indicates the particle diameter in which 50% by volume of all particles have a larger and 50% by volume a smaller particle diameter.

The polymer dispersions have a variety of uses ten, especially as a surface coating, in paint fabrics, in building and Corrosion protection, in the paper, textile and carpet coating, for latex foam molded parts, in adhesive fen, or for the production of thermoplastic molding compositions. This Uses are also the subject of the invention.

The inventive method is suitable for the production of Various types of polymer dispersions A wide variety of polymers can be used. Furthermore, the Solid content variable within wide limits: with the process can be both low solids and high solids Make dispersions easily. Regarding polymer and  The process according to the invention is therefore very solid flexible.

The method advantageously comes without an expensive one Cooling of the dispersion at the end of the extruder and is and therefore regardless of the boiling point of the water.

The process can also be used to produce the final solid content of the dispersion without additional downstream dilution setting step: the dispersion which ver can, has without subsequent dilution or dispersion in Water the desired water content. Mixing the polymer with the emulsifier, adding the water and adjusting the final water content takes place on a single machine consequences. This makes the process easier and cheaper than the methods of the prior art.

The invention is not based on the following examples limits. They explain the invention.

Examples

A ZSK 40M twin-screw extruder from Werner & Pfleiderer was used. The intermeshing snails turned sensibly, had a diameter of 40 mm and were double-threaded. The extruder was operated at a speed of 800 to 1200 min ^-1 (see tables) and was made up of the following zones:

• - Feed zone with normal conveying screw elements,
• - Melting zone with accumulation elements, mixing elements and kneading elements,
• - first mixing zone with mixing elements and kneading elements,
• - second mixing zone with mixing elements and kneading elements,
• - third and last mixing zone with mixing elements and kneading elements, the melting zone from the first mixing zone and the first mixing zone from the second mixing zone with each supportive elements and through returning ele elements were delimited from one another,
• - Discharge zone with a pressure control valve.

By designing the extruder screws with the mentioned Screw elements formed in the extruder between the Melting zone and the subsequent first mixing zone a ring made of melted polymer (melting ring), which sealed extruder contents towards the feed zone.  

The polymer was gravimetrically fed into the feed zone dosed. Possibly. surface-active substances became gravimetric dosed separately from the polymer into the dosing opening, see table len.

In the mixing zones, water and possibly aqueous solutions of surface-active substances by means of piston metering pumps dosed.

The feed zone was operated at room temperature (cold feed). The The temperatures of the mixing zones can be found in the tables. The The discharge zone was at a temperature below the melting point or softening point of the dispersed polymer, however operated above 100 ° C.

The specified pressure is the absolute pressure on the high pressure side of the pressure control valve.

The stated particle size D ₅₀ is the volume-average particle size as defined above.

The following polymers were used:

A1: Nordel® IP 4725, an EPDM rubber polymer (EPDM = ethylene-propylene-diene) from DuPont Dow Elastomers made from 70% by weight of ethylene, 25% by weight of propylene and 5% by weight of ethyl norbornene.
A2: Kraton® 1650, a styrene-ethylene-butylene-styrene block copolymer (SEBS) from Shell with the structure 16% by weight styrene block, 68% by weight ethylene-butylene block and 16% by weight styrene block.
A3: Polystyrene 168 N, a polystyrene from BASF Aktiengesellschaft with a melt volume rate MVR of 1.5 ml / 10 min. measured at 200 ° C and 5 kg load according to ISO 1133.
A4: Ultramid® B3, a polyamide 6 from BASF Aktiengesellschaft with a viscosity number VZ of 150 ml / g, determined on a 0.5% strength by weight solution in 96% strength by weight sulfuric acid at 25 ° C. according to ISO 307th
A5: Kraton® 1701, a styrene-ethylene-butylene-styrene block copolymer (SEBS) from Shell with the structure of 18% by weight styrene block, 64% by weight ethylene-butylene block and 18% by weight styrene block.

The following surface-active substances were used:

S1: Luwax® S, a montan wax from BASF Aktiengesellschaft with an acid number of 154 and a melting point of about 82 ° C.
S2: potassium oleate.
S3: Emulsifier K 30®, a sodium alkylarylsulfonate from Bayer AG made from technical isomer mixtures.
S4: Mowiol® 8-88, a polyvinyl alcohol from Hoechst with a viscosity of 8 mPa.s, measured as a 4% strength by weight aqueous solution at 20 ° C. according to DIN 53 015 and a degree of hydrolysis (degree of saponification) of 88 mol -%.

Potassium hydroxide KOH was used as an auxiliary.

In the tables, "solution" or "solution." a solution from be matching compound in water, "%" means% by weight and "parts" means parts by weight. Unless otherwise stated, the Feedstocks separated from each other and not as a mixture dosed. V means for comparison.

Table 1

Table 1 illustrates that part of the surfactant sub punch as such was fed into the feed zone; the rest Part was a solution in water in the first mixing zone dosed. By varying the amount of water metered in (here in the first and third mixing zones) were different Solids contents.

Table 2

Table 2 illustrates the variation in extruder speed and dosed amounts of substance. In the feed zone and the three mix Zones were always the same polymers, surface-active Substances, auxiliaries or water metered in, but in under different amounts or concentrations.  

Table 3

Table 3 illustrates the variation in the amount of surfaces active substance S and auxiliary substances that are in the feed zone as well the first and second mixing zones were metered. In the two Different substances S were used in the mixing zone.

Example 9 is for comparison. If there was no upper one in the feed zone surfactant added without the in the second mixing zone increase the metered amount accordingly, so there was no dis persion.  

Table 4

Table 4 illustrates the variation of the polymers A used. Example 13 shows that mixtures of different polymers could be dispersed, here a mixture of EPDM and poly styrene. In Example 14, a wet powder was obtained, one so-called solid dispersion. Solid dispersions can be added add water slightly redisperse.

The examples show that with the inventive method Ren polymer dispersions with very different solids content (between 34 and 66 wt .-%) in a simple manner left. All that was required was a single machine: one Premixing the feed materials or a subsequent down-mixing thin to the desired solids content was also unnecessary like cooling the extruder content below the boiling point of the Water.

Claims (9)

1. A process for the preparation of polymer dispersions with a final solids content of 5 to 95 wt .-%, in which at least one polymer A, at least one surface-active substance S and water are mixed in a twin-screw extruder, the speed of the extruder screws being at least 600 min Is ^-1 and the extruder, viewed in the conveying direction, is essentially constructed from
a feed zone in which the polymer A is metered into the extruder,
a melting zone in which the polymer A is melted into a polymer melt,
a first mixing zone in which part of the water is metered in and mixed with the polymer melt to form a polymer / water mixture,
a last mixing zone in which the remaining part of the water is metered in and mixed with the polymer / water mixture, and
a discharge zone in which the polymer-water mixture is discharged,
the surface-active substance S can be metered into the feed zone, the melting zone, the first or the last mixing zone or in several of these zones of the extruder,
characterized by
that the extruder screws are designed in such a way that a ring of melted polymer A (melt ring) forms in the extruder between the melting zone and the most mixing zone, which seals the content of the subsequent extruder towards the feed zone,
that the discharge zone contains a pressure maintaining device and
that the final solids content of the polymer dispersion is set in the last mixing zone by metering in an appropriate amount of water. 2. The method according to claim 1, characterized in that at least one between the first and the last mixing zone another mixing zone is located, in which a part of the water metered and mixed with the polymer-water mixture. 3. The method according to claims 1 to 2, characterized in net that the extruder screws rotate in the same direction. 4. The method according to claims 1 to 3, characterized in that the speed of the extruder screws is at least 700 min ^-1 . 5. The method according to claims 1 to 4, characterized in net that the mixing zones mixing elements or kneading elements or contain both. 6. The method according to claims 1 to 5, characterized in net that the polymer A is selected from the group of Polyoxymethylenes, polycarbonates, polyesters, polyolefins, Polyacrylates, polymethacrylates, polyamides, vinyl aromatic Polymers, polyarylene ethers, polyurethanes, polyisocyanurates, Polyureas, polylactides, thermoplastic elastomers, halogen-containing polymers, imide group-containing polymers, Cellulose esters, silicone polymers, or their mixtures or Copolymers. 7. The method according to claims 1 to 6, characterized in net that the surface-active substance S is selected from Emulsifiers and protective colloids. 8. polymer dispersions, obtainable by the process according to Claims 1 to 7. 9. Use of the polymer dispersions according to claim 8 as top surface coating, in paints, in building and Corrosion protection, in paper, textile and carpeting layering, for latex foam molded parts, in adhesives or for the production of thermoplastic molding compounds.